Probability of Multiple Failures

Date: 06/20/2002 at 21:56:14
From: Marzineh Farvon
Subject: Complete Probability in Calculus
If a car has 2 headlights with an average lifespan of 2500 hours,
whose probability of failure can be modeled by:
f(t) = 0 if t < 0 ;
f(t) = 1/u e ^(-t/u) if t >= 0;
for the mean value u = 2500, what is the probability that both lamps
will fail within 2500 hours, and what is the probability that both
will fail in a total of 2500 hours?